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/. New YorkEntomol. Soc. 99(1): 132-137, 1991 

THEXARVA OF BLEPHARIDATTA 
(HYMENOPTERA: FORMICIDAE) 

GEORGE C. WHEELER AND JEANETTE WHEELER 

Research Associates, Florida State Collection of Arthropods; 
3358 NE 58th Avenue, Silver Springs, Honda 32688 

Abstract. The larva of the myrmicine genus Blepharidatta is described for the first time and 
illustrated. The genus is transferred from the tribe Ochetomyrmecini to a new tribe Blephari- 
dattini. 



HISTORY 

Wheeler described the genus Blepharidatta in 1 9 1 5 and assigned it to the myrmicine 
tribe Attini; he added, "but it differs so much from the other known genera in the 
structure of the head and especially the 2-jointed club of the antennae, the 4-toothed 
mandible and the regularly arranged setiform hairs on the dorsal surface, that it seems 
necessary to establish a distinct genus for its accommodation. Apart from the head 
the structure of the body is very simple and primitive for an Attiine [sic!] ant, even 
simpler and more primitive than in the genus Proatta, recently established by Forel 
for a unique Sumatran species." Wheeler also described as the type species brasiliensis 
from Para, Brazil. 

Gallardo (1916:319) reported finding several worker ants at Alta Gracia, a moun- 
tain resort ca. 20 mi south of Cordoba, which is in the province of Cordoba, in north- 
central Argentina. 

Emery (1921-1922) placed Blepharidatta in the Dacetini (p. 12) because of its 
"tete cordiforme, echancree par derriere et fort retrecie devant" and separated it 
from the other genera (p. 313) by the "scrobe occupant tout le bord lateral de la tete; 
mandibules courtes, pouvant se croiser." He gave the distribution (p. 315-316) as 
"Bresil: Para. Argentine" and said: "Cette Fourmis a une ressemblance frappante 
avec le genre fossile Hypopomyrmex de 1'ambre de Sicile. M. Wheeler classe le genre 
Blepharidatta parmi les Attini. II me semble avoir bien plus d'affinite avec les Dace- 
tini." 

Wheeler stated (1922:376) that the habits of Blepharidatta are unknown. In his 
key to genera (p. 668) he separated Blepharidatta from all other attine genera by its 
distinct 2-jointed antennal club and its long antennal scrobes. 

In 1953 Brown transferred Blepharidatta to the tribe Ochetomyrmecini because it 
is "very closely related to the species of Wasmannia Forel, differing chiefly in its 
more elongate head with produced posterior angles and in having a long, low petiolar 
node." 

Kempf in 1967 described a second species (B. conops), from Tres Lagoas, Mato 
Grosso State, Brazil. He also placed the genus in the tribe Ochetomyrmecini. 

In 1975 Kempf devoted several pages to prove that Ochetomyrmex and Was- 
mannia could not be in the same tribe and suggested "at least as a provisional solution, 
the transfer of Ochetomyrmex to the Solenopsidine tribal complex, in the sense of 

- 13?- 



1991 LARVA OF BLEPHARIDATTA 133 

Ettershank. Thus the tribe name Ochetomyrmecini (nov. syn.) becomes meaningless, 
and the genera Wasmannia and Blepharidatta are without a tribal name. I refrain 
from coining a new name for these two groups, because it seems that the whole 
classification, generic and tribal, of the lower Myrmicinae needs urgent overhauling." 
Our study of larvae supports the tribal separation of Wasmannia and Ocheto- 
myrmex and the transfer of the latter to tribe Solenopsidini, but we are not about to 
join Kempf s refrain and put Blepharidatta and Wasmannia in the same tribe. We 
prefer to leave Wasmannia in Tribal Limbo, pending the Great Overhaul. 

TRIBES 

Before beginning the study of the larvae, we decided it would be advisable to get 
acquainted with the workers of the tribes involved. Characterizations of tribes are 
generally unsatisfactory, so we supported them by reality, namely examination of 
actual workers in our reference collection. 

In his key (1922:655) Wheeler characterized the Dacetini thus: Clypeus prolonged 
between frontal carinae; head cordate, strongly narrowed in front, its dorsal corners 
not spinose. Antennae 4- to 12-jointed, the last joint being very much longer than 
the preceding; mandibles porrect. 

We characterize the Proattini thus: Monotypic. Antennae 1 2-segmented, not 
clubbed. Head with an antennal scrobe, each dorsal corner produced into three 
tubercles. Dorsum with 10 spines on thorax and three on epinotum. Male with 13- 
segmented antennae and well developed pterostigma. Do not cultivate fungi. Old 
World (Malaysia). 

We characterize Wasmannia thus: Monomorphic. Antennae 11 -segmented, with 
3-segmented club, with terminal segment decidedly predominant. Antennal scrobe 
shallow. Meso-epinotal suture impressed; surface of thorax roughened with sculpture 
only. Epinotum armed with spines. Hairs long and sparse. 

We characterize the adults of tribe Attini as follows: Workers and female: an- 
tennae 1 1 -segmented, without a club. Pterostigma narrow or absent. Worker: mono- 
morphic or polymorphic. Head with antennal scrobe. Thoracic dorsum with spines, 
teeth, bosses or prominent ridges. Male: Antennae usually 1 3-segmented. Cultivate 
fungi. New World. 

We establish a new tribe for Blepharidatta with the name Blepharidattini based 
on worker characters: Monotypic. Monomorphic. Head with deep antennal scrobes 
extending to dorsal corners. Each dorsal corner of head with an angulate tubercle. 
Eyes notably protuberant. Antennae 1 1 -segmented, with a 2-segmented club. Man- 
dibles triangular and 4-toothed, directed ventrally. Thoracic dorsum without im- 
pressed sutures; surface roughened with sculpture only. Epinotal spines long. Petiole 
long and with only a small node or none. Postpetiole small. Hairs sparse, long and 
bristle-like. 

It is difficult to compare a single genus with 1 1 genera of Attini, but it is possible 
to compare Blepharidatta with the most primitive attine genus, Cyphomyrmex. In 
order to facilitate a multiple comparison we prepared a table (see Table 1) of 18 
characters of Blepharidatta, Cyphomyrmex and Wasmannia. Characters 1-5 are 
shared by all three genera; 6 and 7 are shared by Wasmannia and Blepharidatta', 8 
1 are shared by Blepharidatta and Cyphomyrmex; 1 1 and 1 2 are shared by Was- 
mannia and Cyphomyrmex; while 13-18 are different in each genus. 



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JOURNAL OF THE NEW YORK ENTOMOLOGICAL SOCIETY Vol. 99(1) 



Table 1 . Comparison of 1 8 characters of workers of Blepheridatta, Cyphomyrmex and 
Wasmannia. 



Character 


Wasmannia 


Blepharidatta 


Cyphomyrmex 


1. Castes 


monomorphic 


monomorphic 


monomorphic 


2. Mandible 


triangular 


triangular 


triangular 


3. Mandibular 


4 subequal 


4 subequal 


4 subequal 


teeth 








4. Eyes 


moderately large and 


moderately large and 


moderately large 




protruding 


protruding 


and protruding 


5. Antennal seg- 


11 


11 


11 


ments 








6. Epinotal spines 


present 


present 


none 


7. Humeral angles 


dentiform 


dentiform 


rounded 


8. Frontal carinae 


not lobulate below 


lobulate below 


lobulate below 


9. Scrobe 


shallow 


deep 


deep 


10. Sting 


well developed 


vestigial 


vestigial 


1 1 . Dorsal corners 


rounded 


angularly tuberculate 


rounded 


of head 








12. Mesoepinotal 


present 


absent 


present 


suture 








13. Antennal club 


3 -segmented 


2-segmented 


no club 


14. Petiole 


large; node high, nar- 


long; low node pres- 


short, low, wide 




row 


ent or absent 




15. Postpetiole 


normal 


small 


large 


16. Gaster 


1st somite long, oth- 


small 


small, 1st somite 




ers small 




covers others 


17. Body hairs 


long, erect, sparse 


long, bristly, erect on 


appressed, rather 






dorsum 


scale-like 


18. Thoracic sculp- 


rugae only 


rugae and punctures 


bosses or carinae 


ture 









To us, this means that Blepharidatta should be placed in a monotypic tribe, if only 
adult anatomy is considered. However,, taxonomists now maintain that a species 
should be denned by all its characters. 



LARVAE 

In September 1989 we received from Dr. J. Lattke in Caracas, Venezuela a most 
welcome gift of 2 workers and 1 2 larvae of B. brasiliensis. These not only enabled 
us to examine a very rare ant species but to describe a larva new to us and perhaps 
to shed some light on the tribal problem. 

Blepharidatta brasiliensis Wheeler 
Fig. 1 

Length (through spiracles) 1.5-2 mm. Profile attoid; segmentation indistinct; spira- 
cles on T2 0.01 mm in diameter, decreasing gradually to 0.008 mm on AI, and to 
0.006 mm on AVIII. Integument minutely spinulose, the spinules more numerous 



1991 LARVA OF BLEPHARIDATTA 135 






Fig. 1 . Blepharidatta brasiliensis. a, Head in anterior view, x 1 00; b, left mandible in anterior 
view, x625; c, body hair, x 100; d, larva in side view, x30. 

and in short rows on venter of anterior somites and dorsum of posterior somites. 
Body hairs sparse, 0.025-0.125 mm long, slightly curved, tip sometimes flexuous. 
Cranium suboctagonal, widest dorsally; integument of dorsal portion spinulose, the 
spinules minute and in short to long rows. Antennae large, at midlength of cranium, 
each with 3 sensilla, each of which bears a spinule. Head hairs few (ca. 22), very 
short (0.003-0.008 mm long), except for 2 near midline (ca. 0.06 mm long). Labrum 
crescentic, wide and very short, anterior surface with 2 sensilla; ventral surface with 
6 sensilla; posterior surface with numerous rows of minute spinules. Mandible small, 
narrowly subtriangular; apex moderately sclerotized, sharp-pointed and without me- 
dial or superficial teeth. Maxilla with rounded apex (adnate?); palp a short frustum 
with 5 (4 apical and 1 lateral) sensilla; galea tall digitiform with 2 apical sensilla. 
Labium feebly bilobed, with short arcuate rows of minute spinules; palp an irregular 
projection with 5 sensilla; an isolated sensillum between each palp and the opening 
of the sericteries; the latter a transverse slit. Hypopharynx spinulose, the spinules 
minute and in arcuate rows, which are in subtransverse rows. (Material studied: 1 2 
larvae from Alto Rio Mabaca, Amazonas, Venezuela, 21'N, 657'W, alt. 200 m, 
courtesy of J. Lattke.) 

We have characterized the larvae of Attini (1976:60 and 1986:691) as follows: 
Profile attoid. Body almost naked, the few hairs minute to short and largely restricted 
to the ventral surface. Mandibles attoid, surface covered with coarse spinules, which 
are directed apically. 

The larvae of several genera do not conform (see G. C. Wheeler, 1948), but they 
are kept in the Attini because their adults culture fungi. Myrmicocrypta has none of 
the distinctive larval characters, but it has adult characters. Apterostigma and Seri- 
comyrmex have non-attoid mandibles, but adults and all other larval characters 
conform. 

We characterized the larva of Proatta in 1985, but we now characterize it thus: 
Profile pheidoloid. Mandibles amblyoponoid, without spinules. Body hairs sparse, 
generally distributed, short, with tip curved or bifid. 

We characterize the larva of Wasmannia thus: Profile pheidoloid. Body hairs 
sparse; short and denticulate and long unbranched. Mandibles pristomyrmecoid. 

We characterize the larva of Blepharidattini thus: Profile attoid. Mandibles am- 



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JOURNAL OF THE NEW YORK ENTOMOLOGICAL SOCIETY Vol. 99(1) 




Figs. 2-4. Comparison of larvae of Cyphomyrmex, Blepharidatta and Wasmannia. 2. Cy- 
phomyrmex. a, Profile; b, body hair; c, left mandible in anterior view. 3. Blepharidatta. a, 
Profile; b, body hair; c, left mandible in anterior view. 4. Wasmannia. a, Profile; b, 2 types of 
body hairs; c, left mandible in anterior view. 



blyoponoid, with two acute teeth, one apical and one subapical. Body hairs sparse 
and moderately long; generally distributed; unbranched, smooth and slightly curved. 
In Figures 2-4 we compare the larva of a primitive attine (Cyphomyrmex), with 
that of Wasmannia, and with that of Blepharidatta. 

CONCLUSION 

Our overall conclusion is that the tribe Attini comprises the 1 1 fungus-growing 
genera. The genus Proatta remains in the monotypic tribe Proattini. The tribe Ocheto- 
myrmecini is dissolved and the genus Blepharidatta is transferred to a new monotypic 
tribe Blepharidattini. 



LITERATURE CITED 

Brown, W. L. 1953. Characters and synonymies among genera of ants. II. Breviora. Mus. 

Comp. Tool. 18:1-8. 
Emery, C. 1921-1922. Fam. Formicidae. Subfam. Myrmicinae. Genera Insectorum. 397 pp., 

7 pi. P. Wytsman, Tervueren, Belgium. 
Gallardo, A. 1916. Notes systematiques et ethologiques sur les fourmis attines de la Repub- 

lique Argentine. Anal. Mus. Nacion. Hist. Nat. Buenos Ayres 28:317-344. 



1991 LARVA OF BLEPHARIDATTA 137 

Kempf, W. W. 1967. Three new South American ants. Studia Entomol. 10:353-360. 

Kempf, W. W. 1975. Miscellaneous studies on Neotropical ants. VI. Studia Entomol. 18: 
341-380. 

Wheeler, G. C. 1948. The larvae of the fungus-growing ants. Amer. Midland Nat. 40:664- 
689. 

Wheeler, G. C. and Jeanette Wheeler. 1976. Ant Larvae: Review and Synthesis. Mem. En- 
tomol. Soc. Washington No. 7, 108 pp. 

Wheeler, G. C. and Jeanette Wheeler. 1985. The larva of Proatta. Psyche 92:447-450. 

Wheeler, G. C. and Jeanette Wheeler. 1986. Ten-year supplement to "Ant Larvae: Review 
and Synthesis." Proc. Entomol. Soc. Washington 88:684-702. 

Wheeler, W. M. 1915. Two new genera of myrmicine ants from Brazil. Bull. Mus. Comp. 
Zool. 59:483-^91. 

Wheeler, W. M. 1922. The ants collected by the American Museum Congo Expedition. Bull. 
Amer. Mus. Nat. Hist. 45:39-269. 

Received 20 November 1989; accepted 22 May 1990.